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Tailored Partitioning for Healthcare Big Data: A Novel Technique for Efficient Data Management and Hash Retrieval in RDBMS Relational Architectures
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作者 Ehsan Soltanmohammadi Neset Hikmet Dilek Akgun 《Journal of Data Analysis and Information Processing》 2025年第1期46-65,共20页
Efficient data management in healthcare is essential for providing timely and accurate patient care, yet traditional partitioning methods in relational databases often struggle with the high volume, heterogeneity, and... Efficient data management in healthcare is essential for providing timely and accurate patient care, yet traditional partitioning methods in relational databases often struggle with the high volume, heterogeneity, and regulatory complexity of healthcare data. This research introduces a tailored partitioning strategy leveraging the MD5 hashing algorithm to enhance data insertion, query performance, and load balancing in healthcare systems. By applying a consistent hash function to patient IDs, our approach achieves uniform distribution of records across partitions, optimizing retrieval paths and reducing access latency while ensuring data integrity and compliance. We evaluated the method through experiments focusing on partitioning efficiency, scalability, and fault tolerance. The partitioning efficiency analysis compared our MD5-based approach with standard round-robin methods, measuring insertion times, query latency, and data distribution balance. Scalability tests assessed system performance across increasing dataset sizes and varying partition counts, while fault tolerance experiments examined data integrity and retrieval performance under simulated partition failures. The experimental results demonstrate that the MD5-based partitioning strategy significantly reduces query retrieval times by optimizing data access patterns, achieving up to X% better performance compared to round-robin methods. It also scales effectively with larger datasets, maintaining low latency and ensuring robust resilience under failure scenarios. This novel approach offers a scalable, efficient, and fault-tolerant solution for healthcare systems, facilitating faster clinical decision-making and improved patient care in complex data environments. 展开更多
关键词 Healthcare Data Partitioning Relational database Management Systems (RDBMS) Big Data Management Load Balance Query Performance Improvement Data Integrity and Fault Tolerance EFFICIENT Big Data in Healthcare Dynamic Data Distribution Healthcare Information Systems Partitioning Algorithms Performance Evaluation in databases
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社会工作质性评估研究的回顾(1990-2003)对中国社会工作的启示 被引量:8
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作者 石丹理 韩晓燕 邓敏如 《社会》 北大核心 2005年第3期70-100,共31页
Objective: This paper reviewed and examined the quality of all the qualitative evaluation studies indexed by two key search terms of “qualitative” and “evaluation” in the Social Work Abstracts database from 1990 t... Objective: This paper reviewed and examined the quality of all the qualitative evaluation studies indexed by two key search terms of “qualitative” and “evaluation” in the Social Work Abstracts database from 1990 to 2003 against a number of criteria typically adopted in the field of qualitative research. The review led to a dissatisfactory finding of the low quality of many qualitative evaluation studies due to their insensitivity to the following issues: philosophical basis of the study, auditability (detailed documentation of the participants and data collecting procedure), biases (acknowledgement of biases and preoccupation, and steps to deal with them), credibility or trustworthiness (triangulation, peer checking and participant verification of the findings), consistency (reliability consciousness and audit trails), and critical interpretation of the data (alternative explanations, disconfirming evidence, and limitations of the study). It was recommended that researchers be cautious when utilizing findings from the published qualitative evaluation studies; that social workers be sensitive to the issue of quality when conducting qualitative evaluation studies; that researchers be critical when judging the qualitative evaluation studies in social work; that researchers develop a clear set of guidelines for qualitative studies; that social work training institutes design qualified qualitative research courses; that a database of social work in China be established; that researchers be engaged in more qualitative studies that demonstrate high quality; that myths in qualitative research be debunked; and that adequate training for social workers on qualitative evaluation studies be provided. 展开更多
关键词 database Abstracts that search when WORK design the and from AUDIT China This WORK MANY with MORE high for of be to all two The led set on
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About the Databases of Meteorological and Environmental Research
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《Meteorological and Environmental Research》 2025年第1期5-5,共1页
The journal of Meteorological and Environmental Research[ISSN:2152-3940]has been included and stored by the following famous databases:CA,CABI,CSA,EBSCO,UPD,AGRIS,EA,Chinese Science and Technology Periodical Database,... The journal of Meteorological and Environmental Research[ISSN:2152-3940]has been included and stored by the following famous databases:CA,CABI,CSA,EBSCO,UPD,AGRIS,EA,Chinese Science and Technology Periodical Database,and CNKI,as well as Library of Congress,United States. 展开更多
关键词 ISSN Library Congress meteorological environmental research issn environmental research scientific databases United States meteorological research databaseS
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Nomogram for overall survival in ampullary adenocarcinoma using the surveillance,epidemiology,and end results database and external validation
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作者 Jia Yang Zi-Yi Wang +2 位作者 Jing Chen Yao Zhang Lei Chen 《World Journal of Clinical Oncology》 2025年第2期36-51,共16页
BACKGROUND Ampullary adenocarcinoma is a rare malignant tumor of the gastrointestinal tract.Currently,only a few cases have been reported,resulting in limited information on survival.AIM To develop a dynamic nomogram ... BACKGROUND Ampullary adenocarcinoma is a rare malignant tumor of the gastrointestinal tract.Currently,only a few cases have been reported,resulting in limited information on survival.AIM To develop a dynamic nomogram using internal and external validation to predict survival in patients with ampullary adenocarcinoma.METHODS Data were sourced from the surveillance,epidemiology,and end results stat database.The patients in the database were randomized in a 7:3 ratio into training and validation groups.Using Cox regression univariate and multivariate analyses in the training group,we identified independent risk factors for overall survival and cancer-specific survival to develop the nomogram.The nomogram was validated with a cohort of patients from the First Affiliated Hospital of the Army Medical University.RESULTS For overall and cancer-specific survival,12(sex,age,race,lymph node ratio,tumor size,chemotherapy,surgical modality,T stage,tumor differentiation,brain metastasis,lung metastasis,and extension)and 6(age;surveillance,epidemiology,and end results stage;lymph node ratio;chemotherapy;surgical modality;and tumor differentiation)independent risk factors,respectively,were incorporated into the nomogram.The area under the curve values at 1,3,and 5 years,respectively,were 0.807,0.842,and 0.826 for overall survival and 0.816,0.835,and 0.841 for cancer-specific survival.The internal and external validation cohorts indicated good consistency of the nomogram.CONCLUSION The dynamic nomogram offers robust predictive efficacy for the overall and cancer-specific survival of ampullary adenocarcinoma. 展开更多
关键词 Ampullary adenocarcinoma Dynamic nomogram Gastrointestinal tract SURVEILLANCE EPIDEMIOLOGY End results database Survival rate
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Constructing, Mapping, and Analyzing Global Urban Forest Databases Using Hyperlinks: A World of Vast Unevenness and Research Challenges
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作者 Stanley D. Brunn Olena Dronova Mahmuda Sharmin 《Natural Resources》 2025年第1期1-23,共23页
A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking an... A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking and policies related to human/environmental worlds at local, regional, and global scales. Maps are an important part of these innovative and ongoing research approaches. In this context, we consider urban forests a topic meriting more attention of scholars studying the geographic and environmental intersections of the natural sciences with the social sciences and humanities. We construct two innovative knowledge bases, one a conceptual framework based on major themes and concepts related to mapping urban forests using key words of the first 100 results of a Google Scholar query and a second using the number of Google Scholar hyperlinks about mapping urban forests in 244 capital cities. We discovered that the constructed world maps reveal vast global unevenness in our knowledge about urban forests in hyperlink numbers and ratios, results that merit further attention by disciplinary, international and interdisciplinary scholarly communities. 展开更多
关键词 Urban Forests database MAPPING Google Scholar HYPERLINKS DISPARITIES Unevenness
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Using multi-satellite microwave remote sensing observations for retrieval of daily surface soil moisture across China 被引量:9
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作者 Ke Zhang Li-jun Chao +6 位作者 Qing-qing Wang Ying-chun Huang Rong-hua Liu Yang Hong Yong Tu Wei Qu Jin-yin Ye 《Water Science and Engineering》 EI CAS CSCD 2019年第2期85-97,共13页
The objective of this study was to retrieve daily composite soil moisture by jointly using brightness temperature observations from multiple operating satellites for near real-time application with better coverage and... The objective of this study was to retrieve daily composite soil moisture by jointly using brightness temperature observations from multiple operating satellites for near real-time application with better coverage and higher accuracy.Our approach was to first apply the single-channel brightness radiometric algorithm to estimate soil moisture from the respective brightness temperature observations of the SMAP,SMOS,AMSR2,FY3B,and FY3C satellites on the same day and then produce a daily composite dataset by averaging the individual satellite-retrieved soil moisture.We further evaluated our product,the official soil moisture products of the five satellites,and the ensemble mean (i.e.,arithmetic mean) of the five official satellite soil moisture products against ground observations from two networks in Central Tibet and Anhui Province,China.The results show that our product outperforms the individual released products of the five satellites and their ensemble means in the two validation areas.The root mean square error (RMSE ) values of our product were 0.06 and 0.09 m3/m3 in Central Tibet and Anhui Province,respectively.Relative to the ensemble mean of the five satellite products,our product improves the accuracy by 9.1% and 57.7% in Central Tibet and Anhui Province,respectively.This demonstrates that jointly using brightness temperature observations from multiple satellites to retrieve soil moisture not only improves the spatial coverage of daily observations but also produces better daily composite products. 展开更多
关键词 Soil MOISTURE retrieval Passive microwave remote sensing Multiple SATELLITES Surface HYDROLOGY SMAP SMOS AMSR2 FY3B FY3C
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Precipitation Retrieval from Himawari-8 Satellite Infrared Data Based on Dictionary Learning Method and Regular Term Constraint 被引量:2
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作者 Wang Gen Ding Conghui Liu Huilan 《Meteorological and Environmental Research》 CAS 2019年第3期61-65,68,共6页
In this paper,the application of an algorithm for precipitation retrieval based on Himawari-8 (H8) satellite infrared data is studied.Based on GPM precipitation data and H8 Infrared spectrum channel brightness tempera... In this paper,the application of an algorithm for precipitation retrieval based on Himawari-8 (H8) satellite infrared data is studied.Based on GPM precipitation data and H8 Infrared spectrum channel brightness temperature data,corresponding "precipitation field dictionary" and "channel brightness temperature dictionary" are formed.The retrieval of precipitation field based on brightness temperature data is studied through the classification rule of k-nearest neighbor domain (KNN) and regularization constraint.Firstly,the corresponding "dictionary" is constructed according to the training sample database of the matched GPM precipitation data and H8 brightness temperature data.Secondly,according to the fact that precipitation characteristics in small organizations in different storm environments are often repeated,KNN is used to identify the spectral brightness temperature signal of "precipitation" and "non-precipitation" based on "the dictionary".Finally,the precipitation field retrieval is carried out in the precipitation signal "subspace" based on the regular term constraint method.In the process of retrieval,the contribution rate of brightness temperature retrieval of different channels was determined by Bayesian model averaging (BMA) model.The preliminary experimental results based on the "quantitative" evaluation indexes show that the precipitation of H8 retrieval has a good correlation with the GPM truth value,with a small error and similar structure. 展开更多
关键词 Himawari-8(H8) retrieval of PRECIPITATION k-nearest NEIGHBOR (KNN) REGULAR TERM constraints DICTIONARY method Bayesian model average (BMA)
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Multi-Scale Vision Transformer with Dynamic Multi-Loss Function for Medical Image Retrieval and Classification
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作者 Omar Alqahtani Mohamed Ghouse +2 位作者 Asfia Sabahath Omer Bin Hussain Arshiya Begum 《Computers, Materials & Continua》 2025年第5期2221-2244,共24页
This paper introduces a novel method for medical image retrieval and classification by integrating a multi-scale encoding mechanism with Vision Transformer(ViT)architectures and a dynamic multi-loss function.The multi... This paper introduces a novel method for medical image retrieval and classification by integrating a multi-scale encoding mechanism with Vision Transformer(ViT)architectures and a dynamic multi-loss function.The multi-scale encoding significantly enhances the model’s ability to capture both fine-grained and global features,while the dynamic loss function adapts during training to optimize classification accuracy and retrieval performance.Our approach was evaluated on the ISIC-2018 and ChestX-ray14 datasets,yielding notable improvements.Specifically,on the ISIC-2018 dataset,our method achieves an F1-Score improvement of+4.84% compared to the standard ViT,with a precision increase of+5.46% for melanoma(MEL).On the ChestX-ray14 dataset,the method delivers an F1-Score improvement of 5.3%over the conventional ViT,with precision gains of+5.0% for pneumonia(PNEU)and+5.4%for fibrosis(FIB).Experimental results demonstrate that our approach outperforms traditional CNN-based models and existing ViT variants,particularly in retrieving relevant medical cases and enhancing diagnostic accuracy.These findings highlight the potential of the proposedmethod for large-scalemedical image analysis,offering improved tools for clinical decision-making through superior classification and case comparison. 展开更多
关键词 Medical image retrieval vision transformer multi-scale encoding multi-loss function ISIC-2018 ChestX-ray14
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Bioinformatics analyses of differentially expressed genes associated with spinal cord injury:a microarray-based analysis in a mouse model 被引量:4
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作者 Lei Guo Jing Lv +2 位作者 Yun-Fei Huang Ding-Jun Hao Ji-Jun Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第7期1262-1270,共9页
Gene spectrum analysis has shown that gene expression and signaling pathways change dramatically after spinal cord injury,which may affect the microenvironment of the damaged site.Microarray analysis provides a new op... Gene spectrum analysis has shown that gene expression and signaling pathways change dramatically after spinal cord injury,which may affect the microenvironment of the damaged site.Microarray analysis provides a new opportunity for investigating diagnosis,treatment,and prognosis of spinal cord injury.However,differentially expressed genes are not consistent among studies,and many key genes and signaling pathways have not yet been accurately studied.GSE5296 was retrieved from the Gene Expression Omnibus DataSet.Differentially expressed genes were obtained using R/Bioconductor software(expression changed at least two-fold;P < 0.05).Database for Annotation,Visualization and Integrated Discovery was used for functional annotation of differentially expressed genes and Animal Transcription Factor Database for predicting potential transcription factors.The resulting transcription regulatory protein interaction network was mapped to screen representative genes and investigate their diagnostic and therapeutic value for disease.In total,this study identified 109 genes that were upregulated and 30 that were downregulated at 0.5,4,and 24 hours,and 3,7,and 28 days after spinal cord injury.The number of downregulated genes was smaller than the number of upregulated genes at each time point.Database for Annotation,Visualization and Integrated Discovery analysis found that many inflammation-related pathways were upregulated in injured spinal cord.Additionally,expression levels of these inflammation-related genes were maintained for at least 28 days.Moreover,399 regulation modes and 77 nodes were shown in the protein-protein interaction network of upregulated differentially expressed genes.Among the 10 upregulated differentially expressed genes with the highest degrees of distribution,six genes were transcription factors.Among these transcription factors,ATF3 showed the greatest change.ATF3 was upregulated within 30 minutes,and its expression levels remained high at28 days after spinal cord injury.These key genes screened by bioinformatics tools can be used as biological markers to diagnose diseases and provide a reference for identifying therapeutic targets. 展开更多
关键词 nerve REGENERATION spinal cord injury differentially expressed GENES BIOINFORMATICS ANALYSES database for Annotation Visualization and Integrated Discovery ANALYSIS inflammation Kyoto Encyclopedia of GENES and Genomes pathway MICROARRAY transcription factors neural REGENERATION
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中国岩石圈数据模型总体设计 被引量:9
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作者 欧少佳 许惠平 +1 位作者 陈华根 叶娜 《地球学报》 EI CAS CSCD 北大核心 2005年第3期265-270,共6页
基于GIS的中国岩石圈三维结构数据库包含了数据类型各异的12个专业子库内容。存储和管理这些复杂的数据需要一个合理有效的数据模型,以确保数据库中的所有数据对象得到精确和完整的表达。本文讨论岩石圈数据模型的总体设计问题,基本思... 基于GIS的中国岩石圈三维结构数据库包含了数据类型各异的12个专业子库内容。存储和管理这些复杂的数据需要一个合理有效的数据模型,以确保数据库中的所有数据对象得到精确和完整的表达。本文讨论岩石圈数据模型的总体设计问题,基本思路是采用当前成熟的面向对象的软件开发技术和面向对象的地理数据库模型。总库数据模型需要满足扩展性和扩充性的要求。开发中用UML协助分析子库数据,在面向对象的地理数据库中用一个要素数据集来容纳一个子库的空间数据,用数据库表、要素类、关系类、子类、域等概念描述岩石圈研究中的各种概念和信息,形成统一的、空间和属性存储管理一体化的岩石圈数据模型。 展开更多
关键词 GIS UML
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2003年6月30日梅雨锋大暴雨β和γ中尺度结构的双多普勒雷达反演 被引量:38
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作者 周海光 王玉彬 《气象学报》 CAS CSCD 北大核心 2005年第3期301-312,共12页
2003年6月下旬至7月上旬,淮河流域出现了持续强暴雨,文中使用双多普勒雷达三维风场反演技术(MUSCAT)对6月29~30日合肥和马鞍山多普勒雷达探测到的暴雨资料进行了三维风场反演,对暴雨系统的中尺度三维动力结构进行了研究。此次梅雨锋暴... 2003年6月下旬至7月上旬,淮河流域出现了持续强暴雨,文中使用双多普勒雷达三维风场反演技术(MUSCAT)对6月29~30日合肥和马鞍山多普勒雷达探测到的暴雨资料进行了三维风场反演,对暴雨系统的中尺度三维动力结构进行了研究。此次梅雨锋暴雨是由β中尺度辐合带和嵌在辐合带上的γ中尺度涡旋共同作用引起的,辐合带上的波动活动对降水具有重要的触发和维持作用。在强降水时段的前期,无为附近中低层的γ中尺度涡旋在东—西走向的中尺度辐合带上自西向东移动,γ涡旋的移动与主雨区的移动基本同步,γ中尺度波动是该时段暴雨的重要动力因素;与此同时,在雨带的北区,γ中尺度涡旋活动比较频繁,但基本上是局地生消;在后期,西南暖湿气流和西风辐合,形成雨带上空的β中尺度辐合带,辐合带随着降水的减弱而减弱;最后,给出了此次暴雨的三维动力结构。 展开更多
关键词 20036 湿
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高速切削稳定性数据库的研究 被引量:2
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作者 唐委校 艾兴 +1 位作者 姜华 宋清华 《制造技术与机床》 CSCD 北大核心 2005年第6期75-78,共4页
针对当前高速切削技术因缺乏考虑高速切削稳定性的优化切削数据及其工程应用方法而不能科学、有效地控制切削过程振动严重影响加工质量及生产率的瓶颈限制,在对高速切削稳定性理论和实验研究的基础上,设计构建了高速切削稳定性数据库。... 针对当前高速切削技术因缺乏考虑高速切削稳定性的优化切削数据及其工程应用方法而不能科学、有效地控制切削过程振动严重影响加工质量及生产率的瓶颈限制,在对高速切削稳定性理论和实验研究的基础上,设计构建了高速切削稳定性数据库。通过数据库系统结构、功能模块以及应用程序的设计实现,该数据库具有考虑切削稳定性的高速切削数据查询、切削稳定性评价、优化等功能。可为生产企业经济、高效、方便地提供以最大生产率和高加工质量为目标的、优化的稳定切削用量参数,为高速切削加工提供了科学、高效、可操作性强的工程应用方法。 展开更多
关键词
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Content-based image retrieval applied to BI-RADS tissue classification in screening mammography 被引量:1
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作者 Júlia Epischina Engrácia de Oliveira Arnaldo de Albuquerque Araújo Thomas M Deserno 《World Journal of Radiology》 CAS 2011年第1期24-31,共8页
AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classificat... AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classification.METHODS:Breast density is characterized by image texture using singular value decomposition(SVD) and histograms.Pattern similarity is computed by a support vector machine(SVM) to separate the four BI-RADS tissue categories.The crucial number of remaining singular values is varied(SVD),and linear,radial,and polynomial kernels are investigated(SVM).The system is supported by a large reference database for training and evaluation.Experiments are based on 5-fold cross validation.RESULTS:Adopted from DDSM,MIAS,LLNL,and RWTH datasets,the reference database is composed of over 10000 various mammograms with unified and reliable ground truth.An average precision of 82.14% is obtained using 25 singular values(SVD),polynomial kernel and the one-against-one(SVM).CONCLUSION:Breast density characterization using SVD allied with SVM for image retrieval enable the development of a CBIR system that can effectively aid radiologists in their diagnosis. 展开更多
关键词 COMPUTER-AIDED diagnosis CONTENT-BASED IMAGE retrieval IMAGE processing Screening MAMMOGRAPHY SINGULAR value decomposition Support vector machine
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西北干旱区沙尘暴数据库系统介绍 被引量:2
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作者 陈旭辉 陆登荣 冯建英 《干旱气象》 2005年第2期60-63,共4页
本系统应用微软access数据库系统建立了西北沙尘天气数据库,采用C/S结构在数据库环境下编程,设计了数据挖掘系统(数据挖掘机)、资料维护系统、数据接口系统。数据挖掘机实现了一般用户在不了解数据格式的情况下,通过可视化的界面按任意... 本系统应用微软access数据库系统建立了西北沙尘天气数据库,采用C/S结构在数据库环境下编程,设计了数据挖掘系统(数据挖掘机)、资料维护系统、数据接口系统。数据挖掘机实现了一般用户在不了解数据格式的情况下,通过可视化的界面按任意条件对资料进行查询、统计,并通过各种算法对资料进行处理,生成用户需要的资料序列;数据接口系统实现将查询结果以图形、文本文件、绘图格式文件等多种格式输出;资料维护系统实现资料的追加及维护等功能。 展开更多
关键词 西 ACCESS C/S
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Retrieval analysis in total knee arthroplasty
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作者 Emerito Carlos Rodriguez-Merchan William J Ribbans 《World Journal of Orthopedics》 2025年第3期28-34,共7页
Retrieval analysis in total knee arthroplasty(TKA)has been little studied in the literature.A narrative review of the literature to understand the current importance of retrieval analysis in TKA has been conducted.On ... Retrieval analysis in total knee arthroplasty(TKA)has been little studied in the literature.A narrative review of the literature to understand the current importance of retrieval analysis in TKA has been conducted.On August 27,2024,a literature search was performed in PubMed using“TKA retrieval analysis”as keywords.A total of 160 articles were found,of which only 19 were analyzed because they were directly related to the subject of this article.Rotating-platform(mobile-bearing)TKA has no surface damage advantage over fixed-bearing TKA.TKAs with central locking mechanisms are more prone to debond from the cement mantle.No major wear of the polyethylene(PE)component in TKA using oxidized zirconium components occurs.Femoral components of cobalt-chromium roughen more than oxidized zirconium femoral components.The use of a polished tibial tray over an unpolished design is advised.At short-run assessment(15 months on average),antioxidant-stabilized highly crosslinked PE components are not clinically different in surface damage,density of crosslinking,or oxidation compared to standard remelted highly crosslinked PE components.A correlation between implant position and PE component surface damage has been reported.It shows the importance of optimizing component position to reduce PE component damage.Contemporary knee tumor megaendoprostheses show notable volumetric metal wear originated at the rotating hinge.Retrieval analysis in TKA renders relevant data on how different prosthetic designs described in the literature perform.Such information can help to improve future prosthetic designs to increase prosthetic survival. 展开更多
关键词 Total knee arthroplasty retrieval analysis RESULTS KNEE ORTHOPEDICS
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Joint Retrieval of PM_(2.5) Concentration and Aerosol Optical Depth over China Using Multi-Task Learning on FY-4A AGRI
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作者 Bo LI Disong FU +4 位作者 Ling YANG Xuehua FAN Dazhi YANG Hongrong SHI Xiang’ao XIA 《Advances in Atmospheric Sciences》 2025年第1期94-110,共17页
Aerosol optical depth(AOD)and fine particulate matter with a diameter of less than or equal to 2.5μm(PM_(2.5))play crucial roles in air quality,human health,and climate change.However,the complex correlation of AOD–... Aerosol optical depth(AOD)and fine particulate matter with a diameter of less than or equal to 2.5μm(PM_(2.5))play crucial roles in air quality,human health,and climate change.However,the complex correlation of AOD–PM_(2.5)and the limitations of existing algorithms pose a significant challenge in realizing the accurate joint retrieval of these two parameters at the same location.On this point,a multi-task learning(MTL)model,which enables the joint retrieval of PM_(2.5)concentration and AOD,is proposed and applied on the top-of-the-atmosphere reflectance data gathered by the Fengyun-4A Advanced Geosynchronous Radiation Imager(FY-4A AGRI),and compared to that of two single-task learning models—namely,Random Forest(RF)and Deep Neural Network(DNN).Specifically,MTL achieves a coefficient of determination(R^(2))of 0.88 and a root-mean-square error(RMSE)of 0.10 in AOD retrieval.In comparison to RF,the R^(2)increases by 0.04,the RMSE decreases by 0.02,and the percentage of retrieval results falling within the expected error range(Within-EE)rises by 5.55%.The R^(2)and RMSE of PM_(2.5)retrieval by MTL are 0.84 and 13.76μg m~(-3)respectively.Compared with RF,the R^(2)increases by 0.06,the RMSE decreases by 4.55μg m~(-3),and the Within-EE increases by 7.28%.Additionally,compared to DNN,MTL shows an increase of 0.01 in R^(2)and a decrease of 0.02 in RMSE in AOD retrieval,with a corresponding increase of 2.89%in Within-EE.For PM_(2.5)retrieval,MTL exhibits an increase of 0.05 in R^(2),a decrease of 1.76μg m~(-3)in RMSE,and an increase of 6.83%in Within-EE.The evaluation suggests that MTL is able to provide simultaneously improved AOD and PM_(2.5)retrievals,demonstrating a significant advantage in efficiently capturing the spatial distribution of PM_(2.5)concentration and AOD. 展开更多
关键词 AOD PM_(2.5) FY-4A multi-task learning joint retrieval
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Secure Medical Image Retrieval Based on Multi-Attention Mechanism and Triplet Deep Hashing
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作者 Shaozheng Zhang Qiuyu Zhang +1 位作者 Jiahui Tang Ruihua Xu 《Computers, Materials & Continua》 2025年第2期2137-2158,共22页
Medical institutions frequently utilize cloud servers for storing digital medical imaging data, aiming to lower both storage expenses and computational expenses. Nevertheless, the reliability of cloud servers as third... Medical institutions frequently utilize cloud servers for storing digital medical imaging data, aiming to lower both storage expenses and computational expenses. Nevertheless, the reliability of cloud servers as third-party providers is not always guaranteed. To safeguard against the exposure and misuse of personal privacy information, and achieve secure and efficient retrieval, a secure medical image retrieval based on a multi-attention mechanism and triplet deep hashing is proposed in this paper (abbreviated as MATDH). Specifically, this method first utilizes the contrast-limited adaptive histogram equalization method applicable to color images to enhance chest X-ray images. Next, a designed multi-attention mechanism focuses on important local features during the feature extraction stage. Moreover, a triplet loss function is utilized to learn discriminative hash codes to construct a compact and efficient triplet deep hashing. Finally, upsampling is used to restore the original resolution of the images during retrieval, thereby enabling more accurate matching. To ensure the security of medical image data, a lightweight image encryption method based on frequency domain encryption is designed to encrypt the chest X-ray images. The findings of the experiment indicate that, in comparison to various advanced image retrieval techniques, the suggested approach improves the precision of feature extraction and retrieval using the COVIDx dataset. Additionally, it offers enhanced protection for the confidentiality of medical images stored in cloud settings and demonstrates strong practicality. 展开更多
关键词 Secure medical image retrieval multi-attention mechanism triplet deep hashing image enhancement lightweight image encryption
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Efficient Reconstruction of Spatial Features for Remote Sensing Image-Text Retrieval
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作者 ZHANG Weihang CHEN Jialiang +3 位作者 ZHANG Wenkai LI Xinming GAO Xin SUN Xian 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第1期101-111,共11页
Remote sensing cross-modal image-text retrieval(RSCIR)can flexibly and subjectively retrieve remote sensing images utilizing query text,which has received more researchers’attention recently.However,with the increasi... Remote sensing cross-modal image-text retrieval(RSCIR)can flexibly and subjectively retrieve remote sensing images utilizing query text,which has received more researchers’attention recently.However,with the increasing volume of visual-language pre-training model parameters,direct transfer learning consumes a substantial amount of computational and storage resources.Moreover,recently proposed parameter-efficient transfer learning methods mainly focus on the reconstruction of channel features,ignoring the spatial features which are vital for modeling key entity relationships.To address these issues,we design an efficient transfer learning framework for RSCIR,which is based on spatial feature efficient reconstruction(SPER).A concise and efficient spatial adapter is introduced to enhance the extraction of spatial relationships.The spatial adapter is able to spatially reconstruct the features in the backbone with few parameters while incorporating the prior information from the channel dimension.We conduct quantitative and qualitative experiments on two different commonly used RSCIR datasets.Compared with traditional methods,our approach achieves an improvement of 3%-11% in sumR metric.Compared with methods finetuning all parameters,our proposed method only trains less than 1% of the parameters,while maintaining an overall performance of about 96%. 展开更多
关键词 remote sensing cross-modal image-text retrieval(RSCIR) spatial features channel features contrastive learning parameter effective transfer learning
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Fusion of Hash-Based Hard and Soft Biometrics for Enhancing Face Image Database Search and Retrieval
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作者 Ameerah Abdullah Alshahrani Emad Sami Jaha Nahed Alowidi 《Computers, Materials & Continua》 SCIE EI 2023年第12期3489-3509,共21页
The utilization of digital picture search and retrieval has grown substantially in numerous fields for different purposes during the last decade,owing to the continuing advances in image processing and computer vision... The utilization of digital picture search and retrieval has grown substantially in numerous fields for different purposes during the last decade,owing to the continuing advances in image processing and computer vision approaches.In multiple real-life applications,for example,social media,content-based face picture retrieval is a well-invested technique for large-scale databases,where there is a significant necessity for reliable retrieval capabilities enabling quick search in a vast number of pictures.Humans widely employ faces for recognizing and identifying people.Thus,face recognition through formal or personal pictures is increasingly used in various real-life applications,such as helping crime investigators retrieve matching images from face image databases to identify victims and criminals.However,such face image retrieval becomes more challenging in large-scale databases,where traditional vision-based face analysis requires ample additional storage space than the raw face images already occupied to store extracted lengthy feature vectors and takes much longer to process and match thousands of face images.This work mainly contributes to enhancing face image retrieval performance in large-scale databases using hash codes inferred by locality-sensitive hashing(LSH)for facial hard and soft biometrics as(Hard BioHash)and(Soft BioHash),respectively,to be used as a search input for retrieving the top-k matching faces.Moreover,we propose the multi-biometric score-level fusion of both face hard and soft BioHashes(Hard-Soft BioHash Fusion)for further augmented face image retrieval.The experimental outcomes applied on the Labeled Faces in the Wild(LFW)dataset and the related attributes dataset(LFW-attributes),demonstrate that the retrieval performance of the suggested fusion approach(Hard-Soft BioHash Fusion)significantly improved the retrieval performance compared to solely using Hard BioHash or Soft BioHash in isolation,where the suggested method provides an augmented accuracy of 87%when executed on 1000 specimens and 77%on 5743 samples.These results remarkably outperform the results of the Hard BioHash method by(50%on the 1000 samples and 30%on the 5743 samples),and the Soft BioHash method by(78%on the 1000 samples and 63%on the 5743 samples). 展开更多
关键词 Face image retrieval soft biometrics similar pictures HASHING database search large databases score-level fusion multimodal fusion
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GMS-5反演湿度场的一维变分质量控制试验 被引量:1
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作者 王华荣 郁凡 桂海林 《气象学报》 CAS CSCD 北大核心 2005年第3期342-350,共9页
应用一维变分方法对GMS5资料反演的相对湿度场进行了变分同化质量控制试验。首先具体分析了1998年6月12~29日的MM5模式12h预报湿度场、卫星反演湿度场和同化分析湿度场的误差统计量(误差平均值、误差自协方差矩阵、均方根误差等)。在... 应用一维变分方法对GMS5资料反演的相对湿度场进行了变分同化质量控制试验。首先具体分析了1998年6月12~29日的MM5模式12h预报湿度场、卫星反演湿度场和同化分析湿度场的误差统计量(误差平均值、误差自协方差矩阵、均方根误差等)。在此基础上,又应用一维变分方法对1998年7月20~30日的资料进行了同化试验,并以1998年7月21日00时(世界时)的结果为例,详细分析比较了3种湿度场。分析结果表明:MM5模式背景湿度场总体上低层偏湿,中上层偏干,各层面上的干湿区域区分明显;但往往湿区过湿,干区又偏干,均方根误差(RMSE)相对较大,各层面多在10以上,最高达到15.6。GMS5卫星反演湿度场总体与探空实测结果更接近,但整体平均看,各个层面基本上略偏湿,特别在中低层,RMSE为6.3~8.9。经过一维变分质量控制的湿度场基本接近卫星反演湿度场,但同化后的湿度场的RMSE在中低层要比卫星反演场的要小,RMSE下降了0.4~0.7,下降比率达到6%~9%;高层与卫星反演结果基本接近。对模式向前12h预报场而言,同化了卫星反演湿度场后,均方根误差值下降了1.4~9.0,下降比率达到17%~59%,同化后的湿度场与实际大气大大接近。 展开更多
关键词 GMS-5 19987 MM5 湿
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